I'm wondering if there is a cheaper way to get from Brussels to Paris by train than Thalys. Thalys prices are alright if you book some time in advance, but it can be quite expensive if you book only a few days before. I don't mind if the travel time takes some extra hours.
This is related to the question “What is the cheapest / fastest way to get from Brussels to Paris?” but no one mentioned other options by train than Thalys there. Perhaps going through Lille is a possibility?
Since December 2024, there is a direct non-high-speed train between Paris and Brussels, operated by Ouigo, taking just over 3 hours. There are 3 services every day. The cheapest advertized price is 10€ but you have to book weeks in advance to get it. The maximum price is 59€, which is still cheaper than chaining regional trains.
The existence of this train is somewhat unusual for long distances in France, so I'm leaving the original answer that was valid for the past 10 years below.
Yes, you can travel with regional trains. It takes a little over 4 hours plus the connection times, and there are no good connections, so count on 5 to 6 hours for the journey. The bus takes 4–5 hours and is cheaper than regional trains.
It isn't easy to find the train times or prices because online planners tend to go for the fastest journey only. There's an option to avoid ICE on the German railways site, which avoids other high-speed trains such as Thalys (currently — it didn't in the past). If you can't get a list of local trains connections, look up Bruxelles–Lille, Lille–Amiens and Amiens–Paris separately.
As of today, you can break your journey as follows:
That's a total of 65.30€. It should be a little less if you go to a train station and buy a single ticket (I don't think you can buy that ticket online).
In comparison, a last minute Thalys ticket costs 99€ and the journey is only 82min. If I elect to travel one day later I find seats for 69€ (obviously this depends on how full the trains are). A last minute ticket on Idbus costs 39€ for a 4-hour journey or 29€ for a 5-hour journey, with no break of journey either way. So regional trains don't seem like a good compromise between price, comfort and speed.
@Gilles already has a very nice answer and mine is on the same line, although the route differs. I have travelled a lot between brussels and Paris avoiding the Thalys by train.
The quickest route involves some high speed connection, from Lille Flanders to Paris. Either on Tuesday or Thursday the SNCF publishes last-minute offers. It has been a while I have been monitoring their offers, that is why I can't be precise on it being tuesday or thursday. The connection between Lille and Paris is quite often mentioned as a last minute.
For both of my suggestion you need to get into Lille from Brussels. 1. As Gilles already mentioned you can use ticket, but there is a cheaper solution in the Railpass (>26 years old) or the Gopass (<26 old). These two passes entitle you to 10 unlimited trips in Belgium. As such only relevant if you plan to do more trips in Belgium.
So depending on your age, you can get to the French border for either 5 or 7 Euro. From the Border you need another ticket.
If you secured a "derniere minute" offer from the SNCF you need to buy a ticket from Mouscron to Lille (6,20 Euro). While writing this answer I could get from Lille to Paris by TGV for 25 Euro for tomorrow, so it is definitely worth looking at.
When I didn't find a good offer for the tgv, I went through Maubeuge. There is a train going to Maubeuge from Lille every hour and there are frequent direct intercity's from Maubeuge to Paris (Gare du Nord), which costs 45,80 Euro.
So would I need to travel tomorrow I would pay for 1. 7,10+6,20 + 25 = 38,30 2. 7,10+6,20+ 45,80 = 59,10
As you can see my route through Maubeuge is slightly more expensive then @Gilles route through Amiens if you use the railpasses and border crossing ticket in stead of buying one ticket form Lille to Brussels.
